X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsan.cpp;h=222a10431be9a74f5f77223376739e87172de0a5;hp=68515170e1d214b572a48dfff45c9b6daa2dc39e;hb=c97104e8540b72ee2c6c9c13d3773d2c0f9ec32f;hpb=a0aa8e760a892ccc7fe994a654074dc12f252f6e

diff --git a/src/san.cpp b/src/san.cpp
index 68515170..222a1043 100644
--- a/src/san.cpp
+++ b/src/san.cpp
@@ -1,17 +1,18 @@
 /*
-  Glaurung, a UCI chess playing engine.
-  Copyright (C) 2004-2008 Tord Romstad
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
+  Copyright (C) 2008 Marco Costalba
 
-  Glaurung is free software: you can redistribute it and/or modify
+  Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
-  
-  Glaurung is distributed in the hope that it will be useful,
+
+  Stockfish is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
-  
+
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
@@ -30,6 +31,7 @@
 #include "movepick.h"
 #include "san.h"
 
+extern SearchStack EmptySearchStack;
 
 ////
 //// Local definitions
@@ -48,8 +50,8 @@ namespace {
 
 
   /// Functions
-  
-  Ambiguity move_ambiguity(Position &pos, Move m);
+
+  Ambiguity move_ambiguity(const Position& pos, Move m);
   const std::string time_string(int milliseconds);
   const std::string score_string(Value v);
 }
@@ -60,206 +62,222 @@ namespace {
 ////
 
 /// move_to_san() takes a position and a move as input, where it is assumed
-/// that the move is a legal move from the position.  The return value is
+/// that the move is a legal move from the position. The return value is
 /// a string containing the move in short algebraic notation.
 
-const std::string move_to_san(Position &pos, Move m) {
-  std::string str;
+const std::string move_to_san(const Position& pos, Move m) {
 
   assert(pos.is_ok());
   assert(move_is_ok(m));
 
-  if(m == MOVE_NONE) {
-    str = "(none)";
-    return str;
-  }
-  else if(m == MOVE_NULL) {
-    str = "(null)";
-    return str;
-  }
-  else if(move_is_long_castle(m))
-    str = "O-O-O";
-  else if(move_is_short_castle(m))
-    str = "O-O";
-  else {
-    Square from, to;
-    Piece pc;
-
-    from = move_from(m);
-    to = move_to(m);
-    pc = pos.piece_on(move_from(m));
-
-    str = "";
-
-    if(type_of_piece(pc) == PAWN) {
-      if(pos.move_is_capture(m))
-        str += file_to_char(square_file(move_from(m)));
-    }
-    else {
-      str += piece_type_to_char(type_of_piece(pc), true);
-
-      Ambiguity amb = move_ambiguity(pos, m);
-      switch(amb) {
-
-      case AMBIGUITY_NONE:
-        break;
-
-      case AMBIGUITY_FILE:
-        str += file_to_char(square_file(from));
-        break;
+  std::string san = "";
 
-      case AMBIGUITY_RANK:
-        str += rank_to_char(square_rank(from));
-        break;
-
-      case AMBIGUITY_BOTH:
-        str += square_to_string(from);
-        break;
-
-      default:
-        assert(false);
+  if (m == MOVE_NONE)
+      return "(none)";
+  else if (m == MOVE_NULL)
+      return "(null)";
+  else if (move_is_long_castle(m))
+      san = "O-O-O";
+  else if (move_is_short_castle(m))
+      san = "O-O";
+  else
+  {
+      Piece pc = pos.piece_on(move_from(m));
+      if (type_of_piece(pc) != PAWN)
+      {
+          san += piece_type_to_char(type_of_piece(pc), true);
+          Square from = move_from(m);
+          switch (move_ambiguity(pos, m)) {
+          case AMBIGUITY_NONE:
+            break;
+          case AMBIGUITY_FILE:
+            san += file_to_char(square_file(from));
+            break;
+          case AMBIGUITY_RANK:
+            san += rank_to_char(square_rank(from));
+            break;
+          case AMBIGUITY_BOTH:
+            san += square_to_string(from);
+            break;
+          default:
+            assert(false);
+          }
+      }
+      if (pos.move_is_capture(m))
+      {
+          if (type_of_piece(pc) == PAWN)
+              san += file_to_char(square_file(move_from(m)));
+          san += "x";
+      }
+      san += square_to_string(move_to(m));
+      if (move_promotion(m))
+      {
+          san += '=';
+          san += piece_type_to_char(move_promotion(m), true);
       }
-    }
-
-    if(pos.move_is_capture(m))
-      str += "x";
-
-    str += square_to_string(move_to(m));
-
-    if(move_promotion(m)) {
-      str += "=";
-      str += piece_type_to_char(move_promotion(m), true);
-    }
   }
-
   // Is the move check?  We don't use pos.move_is_check(m) here, because
   // Position::move_is_check doesn't detect all checks (not castling moves,
   // promotions and en passant captures).
   UndoInfo u;
-  pos.do_move(m, u);
-  if(pos.is_check())
-    str += pos.is_mate()? "#" : "+";
-  pos.undo_move(m, u);
+  Position p(pos);
+  p.do_move(m, u);
+  if (p.is_check())
+      san += p.is_mate()? "#" : "+";
 
-  return str;
+  return san;
 }
 
 
 /// move_from_san() takes a position and a string as input, and tries to
-/// interpret the string as a move in short algebraic notation.  On success,
+/// interpret the string as a move in short algebraic notation. On success,
 /// the move is returned.  On failure (i.e. if the string is unparsable, or
 /// if the move is illegal or ambiguous), MOVE_NONE is returned.
 
-Move move_from_san(Position &pos, const std::string &movestr) {
+Move move_from_san(const Position& pos, const std::string& movestr) {
+
   assert(pos.is_ok());
-  
-  MovePicker mp = MovePicker(pos, false, MOVE_NONE, MOVE_NONE, MOVE_NONE,
-                             MOVE_NONE, OnePly);
+
+  MovePicker mp = MovePicker(pos, false, MOVE_NONE, EmptySearchStack, OnePly);
 
   // Castling moves
-  if(movestr == "O-O-O") {
-    Move m;
-    while((m = mp.get_next_move()) != MOVE_NONE)
-      if(move_is_long_castle(m) && pos.move_is_legal(m))
-        return m;
-    return MOVE_NONE;
+  if (movestr == "O-O-O" || movestr == "O-O-O+")
+  {
+      Move m;
+      while ((m = mp.get_next_move()) != MOVE_NONE)
+          if (move_is_long_castle(m) && pos.pl_move_is_legal(m))
+              return m;
+
+      return MOVE_NONE;
   }
-  else if(movestr == "O-O") {
-    Move m;
-    while((m = mp.get_next_move()) != MOVE_NONE)
-      if(move_is_short_castle(m) && pos.move_is_legal(m))
-        return m;
+  else if (movestr == "O-O" || movestr == "O-O+")
+  {
+      Move m;
+      while ((m = mp.get_next_move()) != MOVE_NONE)
+          if (move_is_short_castle(m) && pos.pl_move_is_legal(m))
+              return m;
+
     return MOVE_NONE;
   }
 
-  // Normal moves
-  const char *cstr = movestr.c_str();
-  const char *c;
-  char *cc;
-  char str[10];
-  int i;
-
-  // Initialize str[] by making a copy of movestr with the characters
-  // 'x', '=', '+' and '#' removed.  
-  cc = str;
-  for(i=0, c=cstr; i<10 && *c!='\0' && *c!='\n' && *c!=' '; i++, c++)
-    if(!strchr("x=+#", *c)) {
-      *cc = strchr("nrq", *c)? toupper(*c) : *c;
-      cc++;
-    }
-  *cc = '\0';
-
-  size_t left = 0, right = strlen(str) - 1;
-  PieceType pt = NO_PIECE_TYPE, promotion;
+  // Normal moves. We use a simple FSM to parse the san string.
+  enum { START, TO_FILE, TO_RANK, PROMOTION_OR_CHECK, PROMOTION, CHECK, END };
+  static const std::string pieceLetters = "KQRBN";
+  PieceType pt = NO_PIECE_TYPE, promotion = NO_PIECE_TYPE;
+  File fromFile = FILE_NONE, toFile = FILE_NONE;
+  Rank fromRank = RANK_NONE, toRank = RANK_NONE;
   Square to;
-  File fromFile = FILE_NONE;
-  Rank fromRank = RANK_NONE;
-
-  // Promotion?
-  if(strchr("BNRQ", str[right])) {
-    promotion = piece_type_from_char(str[right]);
-    right--;
-  }
-  else
-    promotion = NO_PIECE_TYPE;
-
-  // Find the moving piece:
-  if(left < right) {
-    if(strchr("BNRQK", str[left])) {
-      pt = piece_type_from_char(str[left]);
-      left++;
-    }
-    else
-      pt = PAWN;
+  int state = START;
+
+  for (size_t i = 0; i < movestr.length(); i++)
+  {
+      char type, c = movestr[i];
+      if (pieceLetters.find(c) != std::string::npos)
+          type = 'P';
+      else if (c >= 'a' && c <= 'h')
+          type = 'F';
+      else if (c >= '1' && c <= '8')
+          type = 'R';
+      else
+          type = c;
+
+      switch (type) {
+      case 'P':
+          if (state == START)
+          {
+              pt = piece_type_from_char(c);
+              state = TO_FILE;
+          }
+          else if (state == PROMOTION)
+          {
+              promotion = piece_type_from_char(c);
+              state = (i < movestr.length() - 1) ? CHECK : END;
+          }
+          else
+              return MOVE_NONE;
+          break;
+      case 'F':
+          if (state == START)
+          {
+              pt = PAWN;
+              fromFile = toFile = file_from_char(c);
+              state = TO_RANK;
+          }
+          else if (state == TO_FILE)
+          {
+              toFile = file_from_char(c);
+              state = TO_RANK;
+          }
+          else if (state == TO_RANK && toFile != FILE_NONE)
+          {
+              // Previous file was for disambiguation
+              fromFile = toFile;
+              toFile = file_from_char(c);
+          }
+          else
+              return MOVE_NONE;
+          break;
+      case 'R':
+          if (state == TO_RANK)
+          {
+              toRank = rank_from_char(c);
+              state = (i < movestr.length() - 1) ? PROMOTION_OR_CHECK : END;
+          }
+          else if (state == TO_FILE && fromRank == RANK_NONE)
+          {
+              // It's a disambiguation rank instead of a file
+              fromRank = rank_from_char(c);
+          }
+          else
+              return MOVE_NONE;
+          break;
+      case 'x': case 'X':
+          if (state == TO_RANK)
+          {
+              // Previous file was for disambiguation, or it's a pawn capture
+              fromFile = toFile;
+              state = TO_FILE;
+          }
+          else if (state != TO_FILE)
+              return MOVE_NONE;
+          break;
+      case '=':
+          if (state == PROMOTION_OR_CHECK)
+              state = PROMOTION;
+          else
+              return MOVE_NONE;
+          break;
+      case '+': case '#':
+          if (state == PROMOTION_OR_CHECK || state == CHECK)
+              state = END;
+          else
+              return MOVE_NONE;
+          break;
+      default:
+          return MOVE_NONE;
+          break;
+      }
   }
 
-  // Find the to square:
-  if(left < right) {
-    if(str[right] < '1' || str[right] > '8' ||
-       str[right-1] < 'a' || str[right-1] > 'h')
+  if (state != END)
       return MOVE_NONE;
-    to = make_square(file_from_char(str[right-1]), rank_from_char(str[right]));
-    right -= 2;
-  }
-  else
-    return MOVE_NONE;
 
-  // Find the file and/or rank of the from square:
-  if(left <= right) {
-    if(strchr("abcdefgh", str[left])) {
-      fromFile = file_from_char(str[left]);
-      left++;
-    }
-    if(strchr("12345678", str[left]))
-      fromRank = rank_from_char(str[left]);
-  }
-
-  // Look for a matching move:
+  // Look for a matching move
   Move m, move = MOVE_NONE;
+  to = make_square(toFile, toRank);
   int matches = 0;
-  
-  while((m = mp.get_next_move()) != MOVE_NONE) {
-    bool match = true;
-    if(pos.type_of_piece_on(move_from(m)) != pt)
-      match = false;
-    else if(move_to(m) != to)
-      match = false;
-    else if(move_promotion(m) != promotion)
-      match = false;
-    else if(fromFile != FILE_NONE && fromFile != square_file(move_from(m)))
-      match = false;
-    else if(fromRank != RANK_NONE && fromRank != square_rank(move_from(m)))
-      match = false;
-    if(match) {
-      move = m;
-      matches++;
-    }
-  }
-  
-  if(matches == 1)
-    return move;
-  else
-    return MOVE_NONE;
+
+  while ((m = mp.get_next_move()) != MOVE_NONE)
+      if (   pos.type_of_piece_on(move_from(m)) == pt
+          && move_to(m) == to
+          && move_promotion(m) == promotion
+          && (fromFile == FILE_NONE || fromFile == square_file(move_from(m)))
+          && (fromRank == RANK_NONE || fromRank == square_rank(move_from(m))))
+      {
+          move = m;
+          matches++;
+      }
+  return (matches == 1 ? move : MOVE_NONE);
 }
 
 
@@ -270,34 +288,31 @@ Move move_from_san(Position &pos, const std::string &movestr) {
 /// length of 80 characters.  After a line break, 'startColumn' spaces are
 /// inserted at the beginning of the new line.
 
-const std::string line_to_san(const Position &pos, Move line[], int startColumn,
-                              bool breakLines) {
-  Position p = Position(pos);
+const std::string line_to_san(const Position& pos, Move line[], int startColumn, bool breakLines) {
+
   UndoInfo u;
   std::stringstream s;
   std::string moveStr;
-  size_t length, maxLength;
-
-  length = 0;
-  maxLength = 80 - startColumn;
-
-  for(int i = 0; line[i] != MOVE_NONE; i++) {
-    moveStr = move_to_san(p, line[i]);
-    length += moveStr.length() + 1;
-    if(breakLines && length > maxLength) {
-      s << "\n";
-      for(int j = 0; j < startColumn; j++)
-        s << " ";
-      length = moveStr.length() + 1;
-    }
-    s << moveStr << " ";
+  size_t length = 0;
+  size_t maxLength = 80 - startColumn;
+  Position p(pos);
+
+  for (int i = 0; line[i] != MOVE_NONE; i++)
+  {
+      moveStr = move_to_san(p, line[i]);
+      length += moveStr.length() + 1;
+      if (breakLines && length > maxLength)
+      {
+          s << '\n' << std::setw(startColumn) << ' ';
+          length = moveStr.length() + 1;
+      }
+      s << moveStr << ' ';
 
-    if(line[i] == MOVE_NULL)
-      p.do_null_move(u);
-    else
-      p.do_move(line[i], u);
+      if (line[i] == MOVE_NULL)
+          p.do_null_move(u);
+      else
+          p.do_move(line[i], u);
   }
-
   return s.str();
 }
 
@@ -306,26 +321,26 @@ const std::string line_to_san(const Position &pos, Move line[], int startColumn,
 /// It is used to write search information to the log file (which is created
 /// when the UCI parameter "Use Search Log" is "true").
 
-const std::string pretty_pv(const Position &pos, int time, int depth,
+const std::string pretty_pv(const Position& pos, int time, int depth,
                             uint64_t nodes, Value score, Move pv[]) {
   std::stringstream s;
 
   // Depth
-  s << std::setw(2) << std::setfill(' ') << depth << "  ";
+  s << std::setw(2) << depth << "  ";
 
   // Score
   s << std::setw(8) << score_string(score);
 
   // Time
-  s << std::setw(8) << std::setfill(' ') << time_string(time) << " ";
+  s << std::setw(8) << time_string(time) << " ";
 
   // Nodes
-  if(nodes < 1000000ULL)
-    s << std::setw(8) << std::setfill(' ') << nodes << " ";
-  else if(nodes < 1000000000ULL)
-    s << std::setw(7) << std::setfill(' ') << nodes/1000ULL << 'k' << " ";
+  if (nodes < 1000000ULL)
+    s << std::setw(8) << nodes << " ";
+  else if (nodes < 1000000000ULL)
+    s << std::setw(7) << nodes/1000ULL << 'k' << " ";
   else
-    s << std::setw(7) << std::setfill(' ') << nodes/1000000ULL << 'M' << " ";
+    s << std::setw(7) << nodes/1000000ULL << 'M' << " ";
 
   // PV
   s << line_to_san(pos, pv, 30, true);
@@ -336,82 +351,80 @@ const std::string pretty_pv(const Position &pos, int time, int depth,
 
 namespace {
 
-  Ambiguity move_ambiguity(Position &pos, Move m) {
-    Square from, to;
-    Piece pc;
+  Ambiguity move_ambiguity(const Position& pos, Move m) {
 
-    from = move_from(m);
-    to = move_to(m);
-    pc = pos.piece_on(from);
+    Square from = move_from(m);
+    Square to = move_to(m);
+    Piece pc = pos.piece_on(from);
 
     // King moves are never ambiguous, because there is never two kings of
     // the same color.
-    if(type_of_piece(pc) == KING)
-      return AMBIGUITY_NONE;
+    if (type_of_piece(pc) == KING)
+        return AMBIGUITY_NONE;
 
-    MovePicker mp = MovePicker(pos, false, MOVE_NONE, MOVE_NONE, MOVE_NONE,
-                               MOVE_NONE, OnePly);
+    MovePicker mp = MovePicker(pos, false, MOVE_NONE, EmptySearchStack, OnePly);
     Move mv, moveList[8];
-    int i, j, n;
-
-    n = 0;
-    while((mv = mp.get_next_move()) != MOVE_NONE)
-      if(move_to(mv) == to && pos.piece_on(move_from(mv)) == pc
-         && pos.move_is_legal(mv))
-        moveList[n++] = mv;
-    if(n == 1)
-      return AMBIGUITY_NONE;
-
-    j = 0;
-    for(i = 0; i < n; i++)
-      if(square_file(move_from(moveList[i])) == square_file(from))
-        j++;
-    if(j == 1)
-      return AMBIGUITY_FILE;
-
-    j = 0;
-    for(i = 0; i < n; i++)
-      if(square_rank(move_from(moveList[i])) == square_rank(from))
-        j++;
-    if(j == 1)
-      return AMBIGUITY_RANK;
+
+    int n = 0;
+    while ((mv = mp.get_next_move()) != MOVE_NONE)
+        if (move_to(mv) == to && pos.piece_on(move_from(mv)) == pc && pos.pl_move_is_legal(mv))
+            moveList[n++] = mv;
+
+    if (n == 1)
+        return AMBIGUITY_NONE;
+
+    int f = 0, r = 0;
+    for (int i = 0; i < n; i++)
+    {
+        if (square_file(move_from(moveList[i])) == square_file(from))
+            f++;
+
+        if (square_rank(move_from(moveList[i])) == square_rank(from))
+            r++;
+    }
+    if (f == 1)
+        return AMBIGUITY_FILE;
+
+    if (r == 1)
+        return AMBIGUITY_RANK;
 
     return AMBIGUITY_BOTH;
   }
 
 
   const std::string time_string(int milliseconds) {
+
     std::stringstream s;
+    s << std::setfill('0');
 
-    int hours = milliseconds / (1000 * 60 * 60);
-    int minutes = (milliseconds - hours*1000*60*60) / (60*1000);
-    int seconds = (milliseconds - hours*1000*60*60 - minutes*60*1000) / 1000;
+    int hours = milliseconds / (1000*60*60);
+    int minutes = (milliseconds - hours*1000*60*60) / (1000*60);
+    int seconds = (milliseconds - hours*1000*60*60 - minutes*1000*60) / 1000;
 
-    if(hours)
-      s << hours << ':';
-    s << std::setw(2) << std::setfill('0') << minutes << ':';
-    s << std::setw(2) << std::setfill('0') << seconds;
-    
+    if (hours)
+        s << hours << ':';
+
+    s << std::setw(2) << minutes << ':' << std::setw(2) << seconds;
     return s.str();
   }
 
 
   const std::string score_string(Value v) {
+
     std::stringstream s;
 
-    if(abs(v) >= VALUE_MATE - 200) {
-      if(v < 0)
-        s << "-#" << (VALUE_MATE + v) / 2;
-      else
+    if (v >= VALUE_MATE - 200)
         s << "#" << (VALUE_MATE - v + 1) / 2;
-    }
-    else {
-      float floatScore = float(v) / float(PawnValueMidgame);
-      if(v >= 0)
-        s << '+';
-      s << std::setprecision(2) << std::fixed << floatScore;
+    else if(v <= -VALUE_MATE + 200)
+        s << "-#" << (VALUE_MATE + v) / 2;
+    else
+    {
+        float floatScore = float(v) / float(PawnValueMidgame);
+        if (v >= 0)
+            s << '+';
+
+        s << std::setprecision(2) << std::fixed << floatScore;
     }
     return s.str();
   }
-  
 }